John l



(No Model.)

J,- L. BLACK.

ELECTROMAGNETIC BRAKE.

No. 548,509. Patented Oct. 22, 1895.

Jwi .1 .3300? UNITED STATES PATnr rites.

JOHN L. BLACK, OF ST. LOUIS, MISSOURI, ASSIGNOR TO THE S". LOUIS ELEC- TRIO BRAKE OOMPA NY, or SAME PLACE.

ELECTROMAGNETIC BRAKE.

SPECIFICATION forming part of Letters Application filed May 9, 1894.

To all whom it may concern:

Be it known that I, JOHN L. BLACK, of the city of St. Louis, in the State of Missouri, have invented a certain new and useful Improvement in Electromagnetic Brakes, of which the following is a full, clear, and exact description, reference being had to the accompanying drmvings, forming part of this specification.

My invention relates to an improved electromagnetic brake, wherein an electromagnet is used, the cores of which approach or move in opposite directions toward each other in applying the brakes.

M y invention consists in features of novelty hereinafter fully described, and pointed out in the claim.

Figure I is a bottom view illustrative of my invention and showing it applied to a pair of car-trucks. Fig. 11 is a side elevation. Fig. III is an enlarged longitudinal section of the coil, showing the cores in elevation.

Referring to the drawings, 1 represents a car-truck, which maybe of any ordinary construction or form and which is supplied with the usual brake mechanism.

2 represents an electromagnet and 3 the cores fitting within the magnet, arranged a suificient distance apart, so that when the cores are in their outer or normal position when the brakes are not applied there is a space t between the inner ends of the cores to give the necessary movement for applying the brakes. Each core is provided with means 5 for the attachment of the brake connections 6. Any desirable form of brake connections may be used.

7 represents the rheostat for controlling the flow of the electric current, which may be of any wellhuown or desirable form of construction.

The cylinder is so wrapped as to cause the cores 3 to approach each other when the current is turned on. As the cores approach, their a-tiinity for each other increases and they come close together. The brake-shoes are applied with great force, and the same pressure is exerted on the brakes of one truck Patent No. 548,509, dated October 22, 1895.

Serial No. 510,622. (No model.)

that is exerted on the brakes of the other truck, this being due to the fact that the opening within the magnet is unobstructed, so that each core is permitted to and does move within the magnet a greater or less distance relatively to the distance the other core moves, according to the distance it has to move to exert the same pressure as the other core, and the pressure of the two cores is therefore equalized and is the same.

I am aware that it is old to employ an electromagnet for applying brakes to a vehicle, and I am also aware that it is old to employ two separate and distinct cylinders and cores in a single brake mechanism; but as far as I know I am the first to make a brake consisting of a single electromagnet having an unobstructed opening and having two cores ar ranged to move in opposite directions toward each other in applying brakes.

I do not confine myself to any particular shape in the construction of the coil or in the construction of the cores. The coil might be made in one shape and the cores in another.

The operation of lily-improved brake is as follows: The current is received over the wire 8, passing into the rheostat 7 over wire 9 to the terminal wire 10 of the coil of the electromagnet, then passing several times around the cylinder 2, and passes out at the other terminal wire 11, thence to the ground return-wire 12, causing the cores 3 to become highly magnetic and thus approach. each other and apply the mechanism.

I claim as my invention- In an electro magnetic brake, the combination of a brake mechanism, an electro magand two separate cores, arranged within the opening in the magnet and connected to the brake mechanism; whereby when the current is applied the cores approach each other by moving in opposite direct-ions to a point of equalization, substantially as set forth. JOHN L. BLACK. In presence of WM. V. WoLcoTT, E. S. KNIGHT.

net having an unobstructed central opening, 

